By Dr. Karen Becker:
Osteoarthritis (OA), also called degenerative joint disease (DJD), is a condition in which there is inflammation of the synovium, which is a thin layer of tissue that lines the joints and tendon sheaths. Cells within the synovium secrete fluids that lubricate the joints.
OA is characterized by progressive, long-term, and permanent deterioration of the cartilage surrounding the joints. Arthritis is the term used for inflammation of the joints; osteoarthritis describes chronic joint inflammation caused by deterioration of the joint cartilage.
Primary osteoarthritis typically doesn’t have an identifiable cause. However, there are many causes for secondary OA, including trauma, abnormal wear and tear on the joints and cartilage, or an inherited defect present at birth such as hip dysplasia.
Other causes of secondary OA include:
- Abnormal development of joints, commonly the hip or elbow (exacerbated by irregular growth and development, as well as vaccine reactions)
- Dislocation of the kneecap or subluxation of the kneecap or shoulder
- Osteochondrosis dissecans (OCD), a condition in which a flap of cartilage develops abnormally within the joint
- Obesity, which increases stress on the joints
- Prolonged steroid therapy
- Excessive laxity (looseness) of the joints
Symptoms of osteoarthritis vary and include reduced activity level, occasional lameness, and a stiff gait that gets worse after exercise, long periods of activity, or in cold weather.
Nutritional Intervention for Osteoarthritis
The cells in the synovium produce inflammatory cytokines (small proteins that facilitate signaling between cells). Inflammatory cytokines promote systemic inflammation, but the good news is they are often responsive to therapeutic nutritional intervention, including:
Arachidonic acid is a precursor to the proinflammatory cytokines prostaglandins and leukotrienes, which are elevated in pets with osteoarthritis. EPA (eicosapentaneoic acid), an omega-3 essential fatty acid, reduces levels of arachidonic acid.
In another study of 131 dogs with OA being treated with the drug carprofen for pain, omega-3 supplementation allowed for a reduction in pain medication.2
To achieve systemic anti-inflammatory effects, the recommended intake of EPA is 40 to 100 mg/kg.3
- Glucosamine and chondroitin sulfate
Oral glucosamine and chondroitin sulfate has been demonstrated to control inflammation in other species, as well as in a small group of dogs with induced synovitis (inflammation of the synovial membrane).4
- Green-lipped mussel
Green-lipped mussel is a rich source of omega-3 fatty acids as well as chondroitin sulfate. In a 2013 study of 23 arthritic dogs, dietary supplementation with green-lipped mussel and glucosamine raised blood levels of omega-3 fats and improved lameness.5
- Elk velvet antler
In a study of 38 dogs with OA, supplementation with elk velvet antler (which contains chondroitin sulfate) improved subjective and objective signs of osteoarthritis.6
A resin extract from the Boswellia serrata plant is known for its anti-rheumatic and anti-inflammatory properties. When given at 40 mg/kg to 29 dogs with osteoarthritis, it had a positive subjective effect on pain and lameness.7
This spice, along with its active ingredient, curcumin, has been proven to reduce pain and inflammation alone or in conjunction with other medications.
In one study, curcumin significantly decreased the expression of genes involved in inflammation more effectively than non-steroidal drugs.8
The Importance of Lifetime Weight Management and Muscle Tone for Your Pet
Certainly arthritic pets who are also overweight or obese will have a much more difficult time with pain and mobility than lean animals, but it’s also important to understand that overfeeding young pets may play a role in causing OA. In a lifetime study of Labrador Retrievers, 25 percent of the dogs who were overweight at age 2 developed arthritis of the hip. However, the calorie-restricted (ideal weight) Labs had just a 4 percent occurrence rate.9
By the age of 6, the overweight dogs had 1.5 times the incidence of shoulder arthritis as the calorie-restricted dogs.10
In an 18-week study of 14 overweight dogs with hip dysplasia and arthritis, the dogs were placed on a weight loss program and were evaluated every 2 weeks for 12 weeks then 4 weeks apart for the final 2 visits, with the following results:11
- By visit 3, body weights were significantly decreased from starting weights
- By visit 5, pelvic circumference was significantly reduced from starting measurements
- By the final visit, the dogs had lost on average 8.85 percent of their initial body weight and their pelvic circumference was reduced on average almost 7 percent
- From visit 2 onward, lameness scores for both walking and trotting significantly improved week by week
- At the end of the study, 82 percent of the dogs showed improvement in lameness
These results demonstrate that when an overweight dog reaches about a 6 percent decrease in body weight, lameness is significantly decreased. Additional improvement is seen as additional weight is lost.
Bottom line: an obese dog with osteoarthritis can have noticeable improvement in lameness after losing just 6 to 9 percent of body weight. Maintaining your pet’s muscle tone as he grows older can be difficult due to age-related sarcopenia, or muscle wasting (atrophy).
And while “shrinking” is to be expected, to some extent, as pets move from senior to geriatric, many pet parents assume their pets need less exercise as they age, which is simply incorrect.
To offset how quickly atrophy is occurring in our pets, we actually need to move their bodies more with age. Although the intensity, duration and type of exercise will change with age, daily activity is still crucial to prevent profound musculoskeletal weakness with age.
Muscles are what hold your pet’s frame in place, so maintaining muscle tone will also slow the amount of joint laxity (which causes arthritis) as well.